Milk pump and the like



July 14, 1936. PETERSEN 2,047,330

MILK PUMP AND THE LIKE Filed Sept. 19, 1934 imam? Patented July 14, 1936 MILKPUMFANDTHELIKE Thorvald Petersen; Erie, Pm, assignor to R. G. Wright & Company, Buflalo, N. Y.

Application September s, 1934, Serial No. 744,691 I 6 Claims. (01. 103-103) This invention relates to pumps and the like, and particularly to pumps for milk and similar liquids in which simplicity of construction and easy assembly and disassembly are important in '5 order that the parts of the pump may be easily and thoroughly sterilized betweenruns of the milk or other liquid.

This application is, in part, a continuation of my copending application, Ser. No. 654,904 filed 10 February 2, 1933. I I

An object of the invention is-to provide an improved and simplifledrpump, particularly useful for handling milk and similarliquids, that may be easily assembled and disassembled, with which 15 all parts exposed to the liquid being handled can be made easily and quickly accessible for cleaning and sterilization, and with which all parts,

when disassembled, will be easily portable so that they may be placed in a cleaning solution or 20 sterilized.

Another object of the invention is to provide an improved and simplified pump of the centrifugal type, with which rapid assembly and disassembly of the parts are possible, with which the impeller 25 and its shaft may be quickly and easily removed as a unit from the housing, which may be driven by a member imperfectly aligned with the shaft of the impeller, with which the driving force may be applied to the impeller shaft while allowing 30 limited lateral movements of the free end of the impeller shaft, with which the mounting of the impeller shaft and the sealing of the opening in the housing through which it extends are accomplished in an exceptionally simple and.effective 35 manner, and which will be relatively simple, compact, convenient and inexpensive.

Various other objects and advantages will be apparent from the following description of one embodiment of the-invention, and the novel features will be particularly pointed out hereinafter in the appended claims.

In the accompanying drawing:

= Fig. l' is a side elevation of a motor driven milk pump unit constructed. in accordance with this 45 invention; Y i a Fig. 2 is an end elevation of the same;

Fig. 3 is a longitudinal sectional elevation throughthe pump end of the same;

Fig. 4 is a face elevation of the water lubri- 50 cated bearing and sealing ring;

Fig.5 is a side elevation of the same, partly in section: and

Fig. 6 is a perspective of the. impeller and shaft removed'from the housing.

In the illustrated embodiment of the invention, the improved pump unit includes a base Ill, mounting at one end a motor II and at its other end having an upright wall or abutment I2. The wall or abutment I2 is provided with a passage or aperture I3 extending from face to face thereof, 5 and in approximate axial alignment with the armature shaft I4 of the motor II, the shaft It constituting a driving member'for thepump to be described presently. a

The pump to be operated by the motor I i is shown as of the centrifugal type, but may be of other types. It includes a housing I5, having therein a working chamber I6 containing a suitable impeller Il, the impeller being provided with a shaft or stud I8 extending endwise therefrom through an aperture or opening I9 in one end wall of the housing. This end wall 20 is provided with a boss 2| surrounding and defining the aperture I9, the boss projecting outwardly from the end wall 20 and nesting inone end of 20 the passage or aperture I3 in the-upright wall I2 of the base unit Ill. The end wall 20 thus abuts face to face against an upright face or surface of the upright wall I2, and is held against lateral displacement on the wall I2 by the engagement of. the boss 2| in the passage I3 of the wall II.

The wall 20 is provided with a peripheral, annular flange 22 which has a telescoping fit with the other section of the housing I5, a gasket 23 being interposed between the two housing sec tions so as to seal the joint between the two, when the housing sections are forced together face to face. The housing I5 is thus split in a direction crosswise of the axis of the shaft I8, at a point through the working chamber I6, so that "when the housing sections are separated from one another, the impeller I l is exposed and accessible, and'its shaft I8 may then be-removed as a unit entirely from the housing by drawing the shaft 40 I8 through the passage I3 and boss 2|.

A tubular conduit 24 extends from the other end wall of the housing I5 that is opposite from the end wall 20, in approximate axial alignment with the shaft I8 and thus serves as an intake conduit'leading to the working chamber I6. The outer end of this conduit 24 is threaded or otherwise fltted for connection to a coupling 25 by which it maybe quickly and easily attached to or detached from a milk or other liquid supply pipe 26. A clamp arm 2I-ls hinged by pin 28 to a lug 29 onth'e base ID at the lower end of the wall I2, and may be swung into a position in which it extends approximately parallel to but spaced from the wall I2, with the housing I5 disalignment with the shaft I3.

posed between it and the wall l2, as shown in Fi 3.

The arm 21 is provided with an opening 33 through which the tubular conduit 24 of the housing l5 loosely extends, and the upper end of the arm 21 is provided with an end notch or slot 3| into and out of which a threaded arm 32 may swing. The arm 32 is hinged by a pin 33 to the upper end of the wall I2, and at its free end carries a nut 34 which, when the arm 22 is swung into the notch or slot 3|, may be tightened to draw the arm 21 toward the wall I 2 and to clamp the pump housing I! flrmly against the wall |2.

The arm 21 is provided with side flanges 35' which bear against the housing I! at some distance from the tubular conduit 24 thereof, and effectively clamp the housing sections together in telescopic relation and against the wall l2, with the boss 2| in the passage |3 of the wall l2. A tube 36 extends approximately tangentially from the housing l5 and serves as a discharge outlet for the pump. This tube 36, at its free end, is threaded or otherwise suitably formed to receive a detachable coupling 31 by which it may be easily and quickly attached to or detached from a pipe 38 that conducts away the liquid delivered by the pump.

The stud or shaft l8, at its inner end, unites with the impeller IT by a tapered or frusto-conical seat or shoulder 39 which is inclined to the axis of the shaft, and the end wall 20 of the housing merges into the boss 2| by a similar, frusto-conical seat or face 40 which faces the seat 39 and is similarly inclined to the axis of the shaft l8. A combined sealing and bearing ring 4|, shown separately in the Figs. 4 and 5, is disposed between the seats 39 and 40 and may advantageously be approximately rhomboidal in cross section. This ring 4|, particularly when the pump is used for water, milk and similar liquids, is made of a material that is lubricated by water. Examples of such materials are well known in the art, but among them may be mentioned lignum-vitae, hard and semi-hard rubbers, condensation resins, phenolic resins, vulcanized fibers, waxed cardboard and casein compounds and the like. Such bearing and sealing rings are sometimes referred to as water-lubricated or oilless bearing rings, and require no lubrication except that of the liquid being handled which may be water or milk. Such a ring disposedin this manner between the two frustoconical seats functions as a single, combined radial and end thrust bearing between the shaft and the housing, as well as a sealing ring between the shaft and the housing, yet the shaft l8 can rock laterally, at its free end, to some extent so that the bearing ring 4| acts also as a universal bearing for the shaft, insuring a good seal at the aperture IS. The extreme free-end portion 42 of the shaft I3 is reduced in diameter and loosely telescopes into the open end of a sleeve 43, which fits over and forms an extension of the driving member or motor shaft l4 that is disposed in approximate end to end The sleeve 43 is fixed on the shaft H in any desired manner, and a helical spring 44 surrounds the sleeve 43 and is anchored at one end to the sleeve in any desired manner, with the spring 44 extending endwise upon the member l4 and the sleeve 43.

The portion of the helical spring 44 intermediate of its ends is made preferably somewhat larger than the shaft l3 and sleeve 43, but is constricted at its end so as to fit closely the sleeve 43 and the shaft l3. The free end of the shaft l3, beginning at the reduced end section 42 and progressing a short distance towards the impeller, is provided with a spiral or helical groove 5 45 which forms a thread progressing a short distance along the shaft IS. The constricted free end of the spring 44 which encircles the shaft I3 is threaded into the groove 45 to the inner end of the groove, and when so threaded 10 to shaft IS the spring 44 is stretched or tensioned endwise to pull the shaft l8 endwise and compress the sealing ring 4| between the opposed seats, so as to seal the opening l9 in the pump housing through which the shaft l8 extends.

The spring 44 provides a flexible driving connection between the member l4 and the shaft l8 so that the member l4 and shaft l3 do not have to be in perfect alignment, and the spring 44 tends to rock the free end of the shaft l3 lat- 20 erally towards a central position in approximate alignment with the member H. The loose, tele-' scopic relation between the reduced section 42 and the sleeve 43 limits the lateral movements of the free end of the shaft I8, yet does not in- 25 terfere with the normal, flexible driving connection between the member l4 and shaft l3, or with the endwise urge or pull that the spring 44 produces on the shaft IS.

The reduced section 42 is thus made substan- 30 tially smaller than the cavity in the sleeve 43, so there is a material clearance between the section 42 and the sleeve 43. Similarly, there is substantial clearance between the shaft l3 and the wall of the passage l3 in the upright wall ,35 I2, so that the shaft |3 will be free to rock laterally on the bearing ring 4| to a considerable extent as limited by the sleeve 43. The shaft I! also has a substantial clearance with the opening or passage l8 through the boss 2| so that the shaft I8 is supported entirely by the single, universal bearing ring 4| which also functions as a sealing ring.

In the use of this improved pumping unit, the motor l4 and the pump are mounted on the base It in the manner shown in the drawing. After a pumping operation, the pump parts which were exposed to the milk or other liquid handled by the pump may be easily taken apart for cleansing and sterilization. To disassemble the pump, the couplings 25 and 31 are disconnected from the conduit 24 and tube 36 respectively, the nut 34 loosened and the arm 32 swung upwardly and to the left in the drawing, which releases the arm 21. The arm 21 is then swung to the right and downwardly into the position shown by dash lines in Fig. 3, which releases the clamping Dressure between sections of the split housing l5,

When arm 21 swings downwardly, the cup-like section of the housing may move away from the end wall 20 which exposes the impeller I1. one then grasps the impeller and rotates it in a direction to unscrew the shaft l8 from the spring 44, after which the impeller and its shaft may be moved endwise and removed as a unit from the end wall 23, and this releases the end wall 20 of the housing which also may be removed from the upright wall l2. The entire pump housing, the impeller and its shaft l3, and the bearing and sealing ring 4|, as well as the gasket 23 are thus 70 separated from one another and from the upright wall |2 so that they may be placed in a cleansing solution or sterilized.

After the parts of the pump have been thorous ly cleaned and sterilized, they may be easily 75 aoeaaso ,and quickly reassembled against the wall I! by placing the ring ll over the shaft l8, passing the shaft through the end wall 20 and then through the passage I3 of the wall l2. The impeller is then rotated to thread the shaft into the constricted free end of the spring 44, the gasket 23 is disposed against the end wall 20 within the flange 22, and the cup-like section of the housing then disposed against the gasket 23 and in telescopic. relation with the flange 22. The arm 2| is also brought, against the housing It to confine it to the wall l2, the arm 32 swung downwardly intothe end notch or slot, 3| of the arm 21, and the nut 34 tightened which clamps the housing sections together and .confines'them to the wall l2. The couplings 25 and 31 are then re-applied to, the conduit 24 and tube 36 respectively to recouple the pump to the liquid conveying pipes of the system, whereupon the pump is ready for use again.

While the pumping unit herein described and illustrated is particularly useful in the handling of milk and similar liquids where, after each run, the pump must be disassembled, thoroughly cleansed and sterilized and then re-assembled, it

,will be understood that within the broader aspects of the invention, the pump may also be a .the milk or other liquid and interfere with proved unit is a simple, effective and practical pump for various purposes, and perfect alignment with the pump shaft and the driving member is unnecessary. When the pump is assembled thereiis no, part thereof, with which the milk or other liquid engages, that cannot be made easily accessible forcleaning and sterilizing, so

that contamination of the milk is avoided. It will be noted, Particularly, that with this arrangement of parts and with this construction, it has been possible to eliminate all graphite and oil lubricated bearings which tend to contaminate easy assembly and disassembly of the pump. It will be. understood that various changes in the materials, details, and arrangements of parts, which have been herein, described and illustrated in order to explain the nature of the invention,

may be made bythose skilled in the art within theprinciple and scope of the invention, as expressed in the appended claims.

I claim as my invention: a .1. A pump for milk andthe like, in which easy assembly and disassembly of parts exposed to contact with the milkare .important to permit of sterilization of thoseLparts, comprising a support having an uprlght'wall with an aperture therethrough, a pump housing having a boss extending outwardly from an end facethereof, said housing abutting endwise against said upright wall and with its said boss entering and positioned by said aperture, releasable means for clamping said housing against said upright wall, an impeller in said housing and having an operating shaft extending outwardly through said boss and through and free of said aperture in said support, said shaft having, at the portion adjacent said impeller and within said housing, a tapered shoulder with the smaller end outermost, said housing boss having, on its inner face, a tapered bearing surface concentric with said shaft, a bearing ring interposed between said tapered surfaces of the shaft and boss, and providing a combined end thrust and radial bearing for said shaft, and driving means releasably connected to the outer end of said shaft for driving it and also yieldingly and continuously urging it,

.said boss entering and positioned by said aperture, an impeller in said housing andghavin an during its rotation, in an endwise direction against said bearing ring, said housing being split, whereby when the housing is released, its sec- .tions may be separated, the impeller and its shaft withdrawn from the housing and 'said bearingv 5 ring and both housing parts removed from said wall for sterilization before reassembly. I

2. A pump for milk and the like in which easy assembly and disassembly of parts exposed to contact with the milk are important to permit of sterilization of those parts, comprising a support having an upright wall with anaperture therethrough, a pump housing having a, boss extending outwardly from an end face thereof, said housing abutting endwise against said upright wall and with its said boss entering and positioned by said aperture, releasable means for clamping said housing against said upright wall, an impeller in said housing and having an operating shaft extending outwardly through said boss and through said aperture in said support, said shaft having, at the end adjacent said impeller and within said housing, a tapered shoulder with the smaller end outermost, said housing boss having, on its inner face, a tapered bearing surface concentric with said shaft, a bearing ring interposed between said tapered surfaces of the shaft and boss, and providing a combined end thrust and. radial bearing for said shaft, driving means-releasably connected to the outer end of .said shaft for driving itand also yieldingly and continuously urging it in an endwise direction against said bearing ring, said housing being split in a direction crosswise of the axis of rotation of said shaft, and a sealing ring between the abutting edges of. the housing sections, whereby when the housing is released, its

sections may be separated, the impeller and its ,housinghaving an outwardlyidrawn bossand an opening through said boss concentric therewith, said housing abutting against said wall and with operating shaft'extendingoutwardly through said boss. and through said wall, oilless bearing means interposed between said shaftand said boss; and

serving to rotatably support said shaft and seal, the space between said shaft and said boss, said housing being split in a direction crosswise of said shaft, whereby when the housing sections are separated said impeller and its shaft may be withdrawn from said housing and said aperture, a clamping bar hinged at one end to said wall, and extending across and bearing upon said housing to clamp said sections together and against said wall, means releasably connected between the free end of said bar and said wall for drawing said 65 bar toward said wall to clamp the housing sections together and againstsaid wall, said, bar having an opening therethrough approximately centrally of said housing, and the outer section of said housing having an inlet conduit extending 70 outwardly therefrom and through said opening in the bar, and' terminating in a pipe coupling, whereby when said bar is released and swung in a direction away from said wall it will carry one 1 housing section therewith as a unit into a posi- 7 '4 aomasotion which exposes the impeller and permits direct withdrawal of it from the other housing section. and driving means releasably connected to the outer end of said impeller shaft for driving it and continuously urging it endwise against said sealing means.

4. A pump for milk and the like in which easy assembly and bly of the parts exposed to contact with the milk are important to permit of sterilization of such parts, comprising a base having an upright wall at one end thereof and with a horizontal aperture in said upright wall, a pump housing having an outwardly drawn boss abutting against the outer end face of said wall,

with said boss entering and positioned by said aperture, means for releasably confining said housing against said wall, an impeller in said housing having a shaft extending therefrom through said boss and said aperture, and having a spiral groove on its periphery at its outer end and beginning at said outer end, said shaft and the inner face of said boss having opposed frustoconical-bearing surfaces within the housing, an oilless bearing ring interposed between said bear- 85 log surfaces and encircling said shaft, so'as to provide a combined radial and end thrust bearing between said shaft and boss, said housing being split in a direction crosswise of said shaft whereby when the housing is released from said 30 wall, its sections may be separated'from one another and said wall, and said impeller and shaft may be withdrawn from the housing and'upright wall, a motor mounted on the other end of said base with its driving shaft extending towards and 35 in approximate alignment with the impeller shaft, a spiral coil spring anchored at one end to the motor drive shaft and at its other end threaded to the spiral groove on the outer end of said impeller shaft, said motor operating in a direc- 40 tion to thread said spring upon said impeller shaft to the inner end of said groove, and then yieldlngly and flexibly driving said impeller shaft while urging said impeller shaft yieldingly and continuously in an endwise direction against said 45 bearing ring, whereby when said housing is opened said impeller may be rotated to unthread its shaft from said spring and then withdrawn from said upright wall and housing for sterilization.

50 5. A pump or the like, comprising a support, a housing disposed against a face of said support and split in a direction generally parallel to said face, said housing and support having interengaging supporting parts by which the housing is 55 supported against lateral displacement on said support and separable therefrom by movement aperture and of a size smaller than said aperture, a sealing ring disposed 'between' said im- 10 peller and housing around said aperture and acting as a combined end thrust and radial bearing for completely supporting said impeller with its shaft. said impeller and its shaft being otherwise free from and unsupported by said housing and 15 support, with the impeller and shaft free to rock laterally from normal position to a limited extent on said ring, and resilient means connected to the outer end of said shaft for imparting rotation to said shaft, for simultaneously urging said 20 shaft endwise in a direction to compress said ring and'seal said aperture, and for yieldingly urging said shaft laterally into said normal position.

6. A pump or the like, comprising a support, a housing disposed against a face of said support and split in a direction generally parallel'to said face, the abutting faces of said housing and support having an interfltting projection and recess attachment which guides the'housing toward and from said support face in a direction approximately normal to said abutting faces and prevents movement of said housing in a direction generally parallel to said abutting faces when the housing is abutting said support, releasable means acting between said support and housing for pressing the sections of said housing together and against said support so as to keep the housing assembled and confined to said support, said housing and support having aligned apertures 40 on their abutting faces, an impeller in said housing and having an operating shaft projecting therefrom through and out of contact with said aligned apertures, a sealing ring in said housing and disposed between said impeller with its shaft and said housing, and acting as a radial and end thrust bearing support for said impeller and its shaft and sealing the housing aperture, and resilient means connected to the outer end of said shaft for imparting rotation to said'shaft for simultaneously urging said shaft endwise in a direction to compress said ring and seal said aperture, and for yieldingly urging said shaft laterally into said normal position.

THORVALD PETERSEN. 

